Abstract: The structure of a new alkaloid, homoharringtonamide, in the crude extract of Cephalotaxus bark is proposed as formula 16 by using tandem mass spectrometric analysis. Similar amide alkaloid compounds, such as cephalotaxamide (6), 11-hydroxycephalotaxamide (9), harringtonamide (14) or isoharringtonamide (15), in which 9,14 and 15 are hitherto unknown, are also detected.